AB treatment of LRTI

Identification of lower respiratory tract infections (LRTI) patients who require antibiotic therapy (AB)

It has been clinically proven that due to the high specificity of PCT for bacterial infection, PCT measurement at low concentrations can help to differentiate patients with clinically relevant LRTI who require antibiotic therapy from those with viral infection or minor bacterial infection who do not require antibiotic treatment. For patients with clinical signs and symptoms of LRTI and low PCT values (< 0.25 µg/L), it is recommended that antibiotics should not be administered. For patients with very low PCT values (< 0.1 µg/L), AB treatment is strongly discouraged (see decision algorithm, Figure 1).

PCT algorithm LRTIFigure 1: PCT cut-offs for the guidance of AB therapy in patients with suspicion for bacterial LRTI


Using this PCT-based decision algorithm patients with infection of viral etiology or self-limiting disease are not unnecessarily exposed to antibiotics.

Thus, AB prescription potentially could be significantly reduced in LRTI patients, especially in those with acute exacerbation of COPD and bronchitis, with similar clinical outcome for both groups (Figure 2).

Impact PCT AB-reduction study comparison
Figure 2:
Impact of PCT-guided treatment algorithm on antibiotic exposure of patients with LRTI: Results of randomized controlled studies



Schuetz P et al. Expert Rev Anti Infect Ther 2010, 8 (5): 575-87

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